Apparatus for increasing the discharge enery of electrical-vibration systems.



E PATENTED MAY 16 1905. f F. BRAUN 61: E. H. RENDAHL. APPARATUS FORINCREASING THE DISCHARGE ENERGY OF ELECTRICAL VIBRATION SYSTEMS.APPLICATION FILED APB.22,-1904.

i No. 790,250.

UNITED STATES Patented May 16, 1905.

PATENT OF BERLIN, GERMANY.

APPARATUSFOR INCREASING THE DISCHARGE ENERGY OF ELECTRICAL-VIBRATIONSYSTEMS.

. SPECIFICATION forming part of Letters Patent No.- 790,250, dated May16, 1905.

Application filed April 22, 1904. Serial No. 204,352,

To aZZ whom it may concern:

Be it known that we, FERDINAND BRAUN,

. doctor of philosophy and professor, a subject of the German Emperor,residing at Strassburg, Alsace, Germany, and RAGNAR I-LKKAN RENDAI-IL,engineer, a sub'ect of the King of Sweden and Norway, resi ing at 13Hollmannstrasse, Berlin, S. W. Germany, have invented a certain new anduseful Improvement in Apparatus for Increasing the Discharge Energy ofElectrical-Vibration Systems, of which the following is a full, clear,and exact description.

This invention relates to wireless signaling systems, and particularlyto the trans mitting apparatus thereof.

It relates especially to such transmitting apparatus in which moreseparate spark-gaps are contained in the oscillating system.

More'particularly it relates to a disposi tion of means with relation tothe spark-gaps by which the charge-potential is distributed adequate tothe length of the spark-gaps, whereby the exciting energy is increasedor the damping of the oscillating system is diminished.

It is well known that the exciting energy of the oscillating system canbe increased by increasing the discharge-potcntial by enlarging thespark-gap but in this way thelimit isvery soonreached. With the increaseof the sparkgap the resistance of the same increases too quickly and outof proportion, thus resulting in great waste of stored energy in thespark itself. If the curve be taken in which the lengths of the sparksbe entered as abscissze and thepotentials as ordinates, it is found thata curve results dependent on the actual construction each time of thespark-gap and essentially on the radius of curvature of the sparkingpole, which curve, with a given length of spark, shows a critical point.The curve shown in the diagram Figure 1 indicates it at-fourmillimeters. The point is indicated bye. This means that with anenlargement of the spark-gap beyond four millimeters the potential atthe poles of the sparkgap no longer increases proportionately to thespark-gap, but more slowly. Measure:

ments of resistance at the same spark-gap have also shown that the curvefor this does not possess such a flaw, but that the resistance of thespark-gap always grows propor- I tionately with the enlargement. Fromthis it follows that it is impossible without great waste of energy(apart from the condition which is always assumed for the maximum ohmicresistance of vibration circuits) to essentially enlarge the dischargeenergy by increasing the spark-gap. On the other hand, it is necessaryto work only with such spark gaps as liebeneath or little above thecritical sparking length. This spark-gap may be termed the unitspark-gap. Now if while observing these proportions a simple sparkgapwhich is larger than is admissible according to the curve shown in Fig.1 be divided lowable limit'a total potential is in general obtained bymeasurements which is smaller than the sum of the separate potentials tobe expected. The cause of this is to be found in the distribution of thetotal potential over the separate spark-gaps not taking place withoutfurther action to the extent demanded by the separate spark-gaps onaccount oftheir sparking length. The following means remove thisdrawback.

Reference is had to the accompanying drawings, in which- Fig. 1 isadiagram alreadyreferred to. Fig. 2 is a diagrammatic view of a simpletransmitter forwireless telegraphy. Fig. 3 is a diagrammatic view oftransmitter in combination with a closed exciting-circuit. Fig. 4 showsa modification of Fig. 3. Figs. 5 and6 are views of spark-gaps incombination with different means for distributing the charge-potential.

In Fig. 2, which represents an open vibration system, (so-called Hertzsystem) the unit spark-gaps f f f are supplied with potentialscorresponding with their sparking tension by means of a parallelarrangement of condensers c c c to each of the different spark-gaps.These condensers have cominto two separate spark-gaps connected inseries which do not separately exceed the alparatively a very smallcapacity. Generally about one hundred centimeters sufiice.

The size of the condensers is such that the potentials arising in themare proportionate to those ofthe sparking lengths to which each separatespark-gap is to be charged. As the sparkgaps are of equal length, thecondens ers are therefore uniform. By means of this sparking andpotential distribution it is possible to bring into play extraordinarilyhigh discharge-potentials, and therefore considerably increaseddischarge energy, in any suitable vibration systems-for instance, alsoin a so-called open or Hertzian vibration system, as here shownwithoutdiminishing the degree of effectiveness.

In the transmitter shown in Fig. 3 the aerial Wire is excited by aclosed oscillatingcircuit, whichicontains the condensersC G C andseveralspark-gapsf 2 In this case the total potential of the threeserial sparkgaps is distributed in a correct manner also bymeans ofcondensers c c 0 On account of: their extraordinarily small capacity theenergy which isself-accumulated in these is so small that it may beneglected as compared with that accumulated in, C 0 C It also followsfrom the small size of. the condensers c c c that. their own inherentvibrations over the sparlcgapsff are different in size from thefundamental vibration of the exciting-circuit, and therefore do notinfluence theinherent number of vibrations of the-main circuit. Inorder,however, to entirely remove any possibility of this, ohmic resistancesor coils of higher self-induction may be inserted in the intermediatewires from the sparkgap to the potential distributers, as shown in Fig.5, which insertions are admissible for the slower charging vibrationofthe source of high potential, but not for the rapid dischargingvibrations. The suitable distribution of the charge-potential over thespark-gaps may also be obtained by means of the larger condensers C CC", contained in the oscillating circuit, as shown in Fig. 4.

By means of large ohmic or inductive resistances w and w points betweenthe condensers O C C are connected with points between the spark-gapsfff Thereby before starting the discharge the potential differencesbetween the condensers are transmitted to the electrodesof thespark-gaps, and therefore all of, the separate spark-gaps act simultaneously at their discharge. The distribution of potential may also beattained, as easily seen, by utilizing self-induction coils which areconnected with one another in series in place of the condensers c 0 0parallel to eachof the partial spark-gaps, as shown in Fig. 6. Thismethod is, however, but little practicable. The secondary self-inductionof the inductor or transformer charging the main condensers (condensersC 0 C Fig. 3) is, in fact, always so calculated that it yields inconjunction with the capacities C C C a number of inherent vibrations,which numher is identical with the periods. of the primary inductor ortransformer. current. Where self-induction coils are used aspotential-distributers, the resultant self-induction of these isconnected in parallel to that of the secondary inductor-coil, wherebythe resonance of the transformer and the inductor is destroyed, whileretaining the primary alternating-current frequency.

Means of more efficiency in place of the condensers c c 0' may consistof large ohmic resistances, which, like the said condensers, may bearranged directly parallel with the respective spark-gaps.

It is without further comment clear that by the before-described meansshunted to the separate spark-gaps all of the unit, sparks actsimultaneously in commoncircle at their discharge.

Having thus. described our invention, the following is what we claim asnew therein and desire tosecure by Letters Patent:

1. Ail-electrical oscillating systemconsisting of an oscillating circuitcontaining several spark-gaps andeleetricalmeans of good conductivityfor the charge-potential and of small conductivity for the dischargevibrations shunted to the separate spark-gaps for distributing thecharge-potential over the separate spark-gaps.

2. An electrical Oscillating system consisting ofan oscillating circuitcontaining several spark-gaps, capacities and means of smallconductivity for-the rapid discharge vibra tion shunted to thcseparatespark-gaps for distributing the charge-potential over the separatespark-gaps.

3. Anelectrical oscillating system consisting ofan oscillating circuitcontaining several spark-gaps, and small capacities of smallconductivity for the rapid discharge vibrations shuntedto the separatesparkgaps for distributing the charge-potential over the separatespark-gaps.

4. An electrical oscillating system consisting of an oscillating circuitcontaining several spark-gaps, and high self-ind u ctions of smallconductivity for the rapid discharge vibrations shunted to the separatespark-gaps for distributing the charge-potential over the separatespark-gaps.

5. A transmitter for wireless telegraphy consisting of an aerialconductor-containim severalv spark-gaps in series, and eleetricrfi meansof good conductivity for the chargepotential and of small conductivityfor the discharge vibrations shunted to the separate spark-gaps fordistributing the charge potentialof the aerial conductor over theseparate s ark-gaps.

6. transmitter for wireless telegraphy consisting of an aerial.conductor containing several spark-gaps in series, and small capacitiesof small conductivity for the discharge vibrations of the aerialconductor shunted to the separate spark-gaps .for distributing the.charge-potential ofithe aerial conductor over the separate sparkaps.

, 7. 'A transmitter for wireless te egraphy consisting of an aerialconductor in connecconsistingof an aerial conductor in connect10n with aclosed excltlng-circult containing severalsparkaps and small capacltlesof small conducti ility for the discharge vibrations shunted to theseparate spark-gaps.

10. In an electrical oscillating system, the combination ofa pluralityof separatesparkgaps in series, of means for charging each separatespark-gap with a potential corresponding to the spark tension of thatsparka b lin witness whereof We hereunto subscribe our names this 12thday of March, A. D. 1904.

FERDINAND BRAUN. RAGNAR HAKAN RENDAHL.

Witnesses GUSTAV SoHwErss, D. BRANDER.

